The present invention generally relates to toilet flush tank mechanisms and more particularly to apparatus including a buoyant flush valve and a control mechanism for controlling buoyancy of the flush valve.
Typical flush tank toilets are designed to use a standard of volume of water to flush a toilet bowl.
In view of the need for water conservation, dual flush toilets have been designed which allow the user the choice of effecting a full flush to disposed of solid wastes or a partial flush to dispose of liquid wastes.
Heretofore, designed dual flushing toilets have been designed which include multiple outlet ports, separate floats and multiple flushing handles.
The disadvantages of the prior art in addition to the utilization of multiple flushing ports and multiple exterior flushing handles includes unreliable mechanisms for use on a consistent basis which may be hard to operate, or costly, and require constant maintenance. Other devices require entry into the water tank for adjustment, which is not conducive to consumer use.
A present invention is directed to a dual flush toilet and further to dual flush toilet apparatus which converts an ordinary one flush tank toilet into a dual flushing toilet and further overcomes the disadvantages of the prior art.
Dual flush apparatus in accordance with the present invention for toilet having a water tank and a discharge port for flushing water into a toilet bowl generally includes a buoyant flush valve for releasably sealing a discharge port. The flush valve includes a cavity for entrapping air to cause the flush valve to remain open after unseating of the flush valve from the discharge port. The flush valve has a weight for causing seating of the flush valve on the discharge port after flushing of water through the discharge port.
A control mechanism is provided and configured for mounting to the water tank with the control mechanism including a handle and a lever which provides a means for interconnecting a handle and the flush valve for unseating the flush valve from the discharge port.
An air valve connected to the handle is pneumatically connected to the flush valve and vents entrapped air in the flush valve cavity at a selected water level within the water tank.
Thus, the control mechanism in accordance with the present invention controls the buoyancy of the flush valve by releasing entrapped air.
More particularly, the apparatus in accordance with the present invention includes a linkage which provides a means for enabling the handle to move the lever in a direction for unseating the flush valve as the handle is pivoted in either of a clockwise direction or a counterclockwise direction. As hereinafter described in greater detail, the directional pivoting of the handle enables either a full flush or a partial flush of water in the tank.
Still more particularly, the air valve in accordance with the present invention includes a body with an inlet and an outlet and a rotor disposed within the body and connected to the handle for pneumatically connecting the inlet and outlet as the handle is pivoted in one of the clockwise and counterclockwise directions and preventing a pneumatic connection between the inlet and the outlet as the handle is pivoted in another of the clockwise and counterclockwise directions. The pneumatic connection is provided by a flexible tube between the inlet and the flush valve, thus when the inlet and outlet are pneumatically connected the control mechanism controls the buoyancy of the flush valve.
In addition, the apparatus in accordance with the present invention includes a depending tube connected to the outlet with the depending tube having a length shorter than a depth of the water tank for enabling air escape from the outlet as the water level in the water tank falls below the selected level. The selected level is determined by a length of the depending tube.
Thus, when the handle is turned (or pivoted) in one of the clockwise or counterclockwise directions establishing a pneumatic connection between the inlet and the outlet and the water level falls below an end of the depending tube, air from the flush valve cavity is vented, thus reducing its buoyancy and causing early closure thereof onto the discharge port. This effects a partial flush. When the handle is turned (or pivoted) in an opposite direction no pneumatic connection is established between the inlet and the outlet, the buoyancy of the flush valve is not vented through the air valve and a full flush of water from the tank through the discharge port occurs.
When the apparatus of the present invention is incorporated to a toilet the invention includes a toilet bowl, a water tank with a discharge port for flushing water into the water bowl and a water valve, including a float, for filling the water tank to a full flushing level.